Principles of data visualization
MACS 40700
University of Chicago
March 29, 2017
Data types

Tables
- Flat table
- Each row is an item
- Each column is an attribute
- Each cell is a value fully specified by the combination of row and column
- Multidimensional table
Networks

Trees

Fields

Geometry
- Shape of items with explicit spatial positions
- 0D
- 1D
- 2D
- 3D
- Maps
Attribute types

Semantics
- Type vs. semantic
- Key vs. value
Anscombe’s quartet
Dataset 1
| 11 |
9 |
7.500909 |
0.8164205 |
Dataset 2
| 11 |
9 |
7.500909 |
0.8162365 |
Dataset 3
| 11 |
9 |
7.5 |
0.8162867 |
Dataset 4
| 11 |
9 |
7.500909 |
0.8165214 |
Anscombe’s quartet
Dataset 1
| (Intercept) |
3.0000909 |
1.1247468 |
2.667348 |
0.0257341 |
| x |
0.5000909 |
0.1179055 |
4.241455 |
0.0021696 |
|
Dataset 2
| (Intercept) |
3.000909 |
1.1253024 |
2.666758 |
0.0257589 |
| x |
0.500000 |
0.1179637 |
4.238590 |
0.0021788 |
|
Dataset 3
| (Intercept) |
3.0024545 |
1.1244812 |
2.670080 |
0.0256191 |
| x |
0.4997273 |
0.1178777 |
4.239372 |
0.0021763 |
|
Dataset 4
| (Intercept) |
3.0017273 |
1.1239211 |
2.670763 |
0.0255904 |
| x |
0.4999091 |
0.1178189 |
4.243028 |
0.0021646 |
|
Anscombe’s quartet

Marks

Channels

How to pick an appropriate graph
- Think about the task or tasks you want to enable
- Try different graphic forms
- Arrange the components of the graphic
- Test the outcomes
What is the story?

Basic charts
- What is the purpose?
- Comparisons
- Proportions
- Relationships
- Location
- Distribution
- Patterns
Box-and-whisker plot

Box-and-whisker plot

Grouped bar chart

Scatterplot

Scatterplot

Line graph

Network diagram

Network diagram

Heatmap
